Flow control valve assembly



Oct. 10, 1961 INVENTORS ALBERT J. GRA/VBERG ERIK r/wsz HIS A TTORNEYS rates Unite Our invention relates to liquid flow valves and more particularly to a flow control valve assembly.

Meters for measuring flow of liquid function most efficiently when the liquid is flowing therethrough at a substantially prescribed rate which may be measured in terms of so many gallons per minute.

The flow control valve assembly of the present invention is installed in the same pipe line which includes the meter, and depending on its location in the line, the valve assembly is adjusted to set the flow rate of liquid to fit the particular meter. When once adjusted, the valve assembly automatically functions thereafter to maintain such prescribed rate of flow, despite changes in the system which might tend to alter the flow rate of the liquid therein.

Among the objects of our invention are:

(1) To provide a novel and improved flow control valve assembly;

(2) To provide a novel and improved control valve assembly which readily compensates for pressure Variations in a flow line;

(3) To provide a novel and improved control valve assembly which may be adjusted for operation in different ranges of pressure.

Additional objects of our invention will be brought out in the following description of a preferred embodiment of the same, taken in conjunction with the accompanying drawings, wherein the figure is a View in section through an improved valve assembly of the present invention.

Referring to the drawings for details of our invention in its preferred form, the flow control valve assembly depicted therein comprises a casing 1 having a flanged inlet 3 and a flanged outlet 5 for the connection of such casing in a pipe line. The intermediate portion of the casing is enlarged to provide for the support therein of a cylinder 7 of a diameter comparable to the inlet of the casing.

This cylinder is supported in axial alignment with the inlet and in spaced relationship thereto, by a plurality of radial ribs or fins 9 extending inwardly from the casing, the cylinder and easing defining the main passage 11 through the valve assembly.

The main valve 13 located within the casing, spans the inlet and includes the skirt 15 closing such main passage. The main valve is adapted to move from its closing position into the cylinder to progressively expose the main passage.

The cylinder includes a transverse wall 17 functioning as a back stop for a compression spring 19 disposed within the cylinder in pressure engagement with the main valve and normally urging such main valve toward its closing position, which may be determined by a spring ring 21 resting in a peripheral groove in the inlet defining Wall.

To accomplish the objects of our invention, we incorporate into the main valve assembly, means for altering the closing effect of the compression spring 19 in response to variations in flow pressure in the vicinity of the outlet of the valve assembly.

Toward this end, we provide the main valve 13 with a hollow valve stem 23 which is slidably supported and guided at its free end, in the transverse Wall 17. At an intermediate point on such valve stem, the stem is pro- Patented Oct. 10, 1961 vided with one or more small orifices 25 to thereby establish communication between the pressure side of the main valve and the region behind the valve which includes the space within the cylinder. This region may be designated the main valve chamber 27.

The cylinder in its rear wall 17 is formed with a hollow protuberance 31 having upper and lower parallel walls 33 and 35 respectively, such walls being drilled to provide aligned openings 37 and 39 therethrough, thereby providing flow communication between the main valve chamber 27 and outlet of the casing. The main valve thereby becomes sensitive to pressure conditions and changes which may occur at the outlet of the casing.

In these aligned openings is disposed the valve component 41 of a supplemental pressure sensitive valve assembly 43. The valve component is of hollow cylindrical form slidably receivable in the aligned openings and having at an intermediate portion, one or more slots 45 so located as to leave the lower portion 47 of the valve of sufficient length to span the spacing between the parallel walls 33 and 35, whereby to completely block communication between the main valve chamber and the outlet of the casing through the aligned openings. With the valve 41 shifted so as to present the full notched openings between the parallel Walls, a full open condition of the valve 41 will be established. In between the fully opened position and the closing position of this valve, the extent of communication between the main valve chamber and the casing outlet may be altered.

This valve 41 is provided with a valve stem extending upwardly through a hole 51 in the casing, to connect with a diaphragm 53 located outside of the casing in a housing formed by a hollow cylinderical section 55 bolted to the casing, the casing being recessed at that location. This hollow cylindrical section provides a chamber for reception of a compression spring 57 resting at one end upon the diaphragm, and held under compression by a threaded closure 59 and an intervening pressure disk 61.

Adjustments of the closure will result in altering the compression of the spring against the diaphragm, and a rubber plug 63 inserted in the threaded wall of the closure, will serve to maintain the closure against accidental tuming and thus hold any adjustment of the spring.

A protective cap 65 may be bolted to the end of the housing section 55, to guard against tampering with adjustments. In the event the closure 59 is provided with an adjustment scale, the cap 65 will preferably be of transparent material such as a transparent plastic.

With the pressure sensitive valve assembly added to and included in the main valve assembly, it will be apparent that the diaphragm 53 will be exposed to pressure conditions within the valve casing at the outlet thereof, and that any fluctuations in pressure in this region will be reflected in corresponding responses of the diaphragm. The degree to which the diaphragm responds will, of course, depend largely upon the pressure adjustment of the spring behind the diaphragm, and this, in turn, will determine the extent to which the diaphragm connected valve 41 Will respond. Adjustment of the compression spring, of course, will depend upon the recording characteristics of the meter installed in the line with the valve assembly and its location in such line, but when once adjusted, the extent to which the diaphragm connected valve will move in response to pressure fluctuations at the outlet will then be determined.

When the flow control valve assembly of the present invention is installed in a pipe line in which a liquid meter is located, the main valve 13 will open in response to initiation of flow of liquid through such line to the meter, the extent to which the main valve will open, depending upon the pressure of the liquid flow against the main valve. Under these conditions, the pressure sensi tive valve assembly will be adjusted so that its diaphragm connected valve will preferably be in partially open position When flow through the meter is at the desired rate.

A portion of the liquid flow striking the main valve will enter the main valve chamber through the valve stem. From the main Valve chamber, such liquid will flow through the diaphragm connected valve to join the main flow through the casing to the meter. The main valve will accordingly open until the frontal pressure is balanced by the spring 19 and prevailing back pressure of liquid in the main valve chamber.

Should the rate of flow of liquid tend to increase for any reason, such as by the inclusion of additional pumps pumping liquid into the line, and thus bring about a tendency for the pressure in the meter to rise, such tendency of the pressure to rise Will reflect itself back in the line to the flow control valve assembly and bring about a response against the diaphragm. Such response will result in the diaphragm moving its associated valve in a direction to more completely block flow through the aligned openings.

This in turn Will result in building up a greater back pressure of liquid behind the main valve, and this coupled with the main valve spring 19, will force movement of the main valve in the direction of its closing position until a new balance of pressures is established on both sides of the main valve. This will cause the main valve to stop in a more nearly closed position, with the result that the pressure at the outlet of the casing will be reduced to its initial value.

Conversely, a lowering of flow rate in the line will bring about a tendency toward a drop in pressure reflected back to the flow control valve, and an opposite sequence of events will take place causing an increased opening of the main valve to re-establish prior pressure conditions at the meter.

In the foregoing manner, any tendency toward fluctuation of pressure at the outlet of the flow control valve assembly will bring about a compensatory movement of the main valve so as to overcome such tendency and maintain pressures at the outlet substantially constant.

From the foregoing description of our invention, in its preferred form, it will be apparent that the objects of our invention will be fully realized and while we have described our invention in considerable detail, the same is subject to alteration and modification without departing from the underlying principles involved, and we accordingly do not desire to be limited in our protection to such details as We have illustrated and described, except as may be necessitated by the appended claim.

We claim:

A flow control valve assembly for use in a pipe line to maintain a substantially constant flow of liquid in such line to a liquid meter installed therein, in spite of variations in flow pressure above or below a desired value on the upstream side of said valve assembly, said flow control valve assembly comprising a casing having a flanged inlet and a flanged outlet for connection of said casing in a pipe line, said casing having an enlarged intermediate portion, a cylinder supported within the enlarged portion of said casing in spaced relationship to the inner wall thereof to provide a main flow passageway through said casing, said cylinder having an open end facing said casing inlet and of a diameter comparable thereto, and a wall at the opposite end thereof facing said casing outlet, a main valve in said casing including a transverse wall adapted to span said casing inlet and having a cylindrical skirt extending from said transverse wall into said casing and slidably receivable in said cylinder and of a length to substantially block said main passageway when said main valve transverse wall is spanning said casing iniet, a hollow valve stem extending at one end centrally through said main valve transverse wall and at its other end slidably supported in said cylinder end wall, said hollow valve stem having an opening through the Wall thereof, a supplemental pressure sensitive valve assembly including a supplemental continuously adjustable valve in said cylinder end Wall, a diaphragm spanning an opening in the wall of said casing in alignment with said continuously adjustable valve, a valve stem connecting said supplemental continuously adjustable valve to said diaphragm, and means for adjusting the extent of opening of said supplemental continuously adjustable valve.

References Cited in the file of this patent UNITED STATES PATENTS 370,886 Patterson Oct. 4, 1887 474,244 Hanson May 3, 1892 489,515 Wood Jan. 10, 1893 802,496 Collin Oct. 24, 1905 845,063 Desper Feb. 26, 1907 1,058,960 Galvin et a1. Apr. 15, 1913 1,987,819 Foulds Jan. 15, 1935 2,067,335 Pardee Jan. 12, 1937 

